JP2021075409A - Method of improving fire resistance of high-strength mortar or high-strength concrete - Google Patents
Method of improving fire resistance of high-strength mortar or high-strength concrete Download PDFInfo
- Publication number
- JP2021075409A JP2021075409A JP2019201252A JP2019201252A JP2021075409A JP 2021075409 A JP2021075409 A JP 2021075409A JP 2019201252 A JP2019201252 A JP 2019201252A JP 2019201252 A JP2019201252 A JP 2019201252A JP 2021075409 A JP2021075409 A JP 2021075409A
- Authority
- JP
- Japan
- Prior art keywords
- strength
- fine powder
- fire resistance
- concrete
- fly ash
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000004570 mortar (masonry) Substances 0.000 title claims abstract description 31
- 239000011372 high-strength concrete Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 14
- 239000000843 powder Substances 0.000 claims abstract description 47
- 239000010881 fly ash Substances 0.000 claims abstract description 32
- 239000011230 binding agent Substances 0.000 claims abstract description 23
- 239000002893 slag Substances 0.000 claims abstract description 21
- 239000004568 cement Substances 0.000 claims abstract description 19
- 239000002245 particle Substances 0.000 claims abstract description 15
- 230000001186 cumulative effect Effects 0.000 claims abstract description 9
- 239000000463 material Substances 0.000 claims description 22
- 238000006467 substitution reaction Methods 0.000 abstract description 8
- 238000002156 mixing Methods 0.000 abstract description 2
- 239000004567 concrete Substances 0.000 description 20
- 239000000835 fiber Substances 0.000 description 14
- 229910021487 silica fume Inorganic materials 0.000 description 13
- 239000004743 Polypropylene Substances 0.000 description 11
- -1 polypropylene Polymers 0.000 description 11
- 229920001155 polypropylene Polymers 0.000 description 11
- 239000000203 mixture Substances 0.000 description 10
- 238000012360 testing method Methods 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000004880 explosion Methods 0.000 description 9
- 230000007423 decrease Effects 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 239000011398 Portland cement Substances 0.000 description 4
- 210000004556 brain Anatomy 0.000 description 4
- 239000002270 dispersing agent Substances 0.000 description 3
- 238000010998 test method Methods 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 230000009970 fire resistant effect Effects 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000002956 ash Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- PAZHGORSDKKUPI-UHFFFAOYSA-N lithium metasilicate Chemical compound [Li+].[Li+].[O-][Si]([O-])=O PAZHGORSDKKUPI-UHFFFAOYSA-N 0.000 description 1
- 229910052912 lithium silicate Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000011150 reinforced concrete Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Building Environments (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
Description
本発明は、高強度モルタルまたは高強度コンクリートの耐火性能を向上させる方法に関するものであり、セメントなどの結合材の一部を高炉スラグ微粉末またはフライアッシュ微粉末に置き換えることにより耐火性能を向上させるようにしたものである。 The present invention relates to a method for improving the fire resistance of high-strength mortar or high-strength concrete, and improves the fire resistance by replacing a part of a binder such as cement with blast furnace slag fine powder or fly ash fine powder. It was made like this.
従来、高炉スラグやフライアッシュ、シリカヒュームを混合した混合セメントが使用されており、それらを用いて、高強度モルタルやコンクリートが製造されている。セメント組成物に配合するためのフライアッシュおよびフライアッシュを用いたモルタルまたはコンクリートに関する従来技術としては、例えば以下の特許文献１〜６記載の発明がある。 Conventionally, mixed cement in which blast furnace slag, fly ash, and silica fume are mixed has been used, and high-strength mortar and concrete are manufactured using them. As a prior art relating to fly ash for blending into a cement composition and mortar or concrete using fly ash, for example, there are inventions described in Patent Documents 1 to 6 below.
特許文献１には、ポルトランドセメントと、ＢＥＴ比表面積が２ｍ２／ｇ以上５ｍ２／ｇ未満であるフライアッシュと、水と、セメント分散剤とを含んでなる超高強度モルタル組成物であって、ポルトランドセメントとフライアッシュとの質量比が９０：１０〜７０：３０であり、水／結合材比が０．１〜０．２であり、セメント分散剤がポリカルボン酸系分散剤を含有していることを特徴とする超高強度モルタル組成物、およびこれに粗骨材が配合された超高強度コンクリート組成物が開示されている。 Patent Document 1 describes an ultra-high-strength mortar composition containing Portland cement, fly ash having a BET specific surface area of 2 m 2 / g or more and less than 5 m 2 / g, water, and a cement dispersant. , Portland cement and fly ash have a mass ratio of 90: 10 to 70:30, a water / binder ratio of 0.1 to 0.2, and a cement dispersant containing a polycarboxylic acid dispersant. An ultra-high-strength mortar composition characterized by the above-mentioned properties and an ultra-high-strength concrete composition in which coarse aggregate is blended are disclosed.
特許文献２には、粉砕して微粒子化したフライアッシュであって、質量平均粒径（μｍ）が０．１乃至０．７３μｍの範囲にあり、かつ粒径３.７３μｍ以下における質量累積率（％）が９５％以上となり、また、ブレーン比表面積が２．５ｍ２／ｇ（２５０００ｃｍ２／ｇ）以上であることを特徴とする多機能性フライアッシュが開示されており、従来のフライアッシュを用いたセメントおよびコンクリート硬化体の早期強度の低下といった問題を克服し、その硬化体の２８日強度並びに長期強度も増進させ、しかもセメント硬化体以外のものにも多用途化できる旨が記載されている。 Patent Document 2 describes a mass accumulation rate (mass accumulation rate) of fly ash crushed into fine particles having a mass average particle size (μm) in the range of 0.1 to 0.73 μm and a particle size of 3.73 μm or less. %) Is 95% or more, and a multifunctional fly ash characterized by a brain specific surface area of 2.5 m 2 / g (25000 cm 2 / g) or more is disclosed. It is stated that it overcomes problems such as a decrease in the early strength of the cement and concrete hardened material used, enhances the 28-day strength and long-term strength of the hardened material, and can be used for various purposes other than the cement hardened material. There is.
特許文献３には、結合材にブレーン比表面積が２５００〜１００００ｃｍ２／ｇのフライアッシュを含む混合物を用いた水結合材比が１０〜２０％の高強度ポーラスコンクリートの開示がある。 Patent Document 3 discloses a high-strength porous concrete having a water binder ratio of 10 to 20% using a mixture containing fly ash having a brain specific surface area of 2500 to 10000 cm 2 / g as a binder.
特許文献４には、セメント、シリカフューム、及び、シリカフュームに比べて大きな粒度を有するフィラー（分級フライアッシュ：ブレーン比表面積は、好ましくは４０００〜５００００ｃｍ２／ｇ、より好ましくは６０００〜３００００ｃｍ２／ｇ、特に好ましくは７０００〜２００００ｃｍ２／ｇである。）も含む結合材を用いた水結合材比０．１８以下であり、圧縮強度が８０Ｎ／ｍｍ２以上のコンクリートからなる耐摩耗版の製造方法の開示がある。 Patent Document 4 describes cement, silica fume, and a filler having a larger particle size than silica fume (classified fly ash: brain specific surface area is preferably 4000 to 50,000 cm 2 / g, more preferably 6000 to 30000 cm 2 / g. Particularly preferably, it is a method for producing a wear-resistant plate made of concrete having a water binder ratio of 0.18 or less and a compressive strength of 80 N / mm 2 or more using a binder containing 7,000 to 20,000 cm 2 / g. There is disclosure.
特許文献５には、特許請求項に粒径２０μｍ以下のフライアッシュを２〜２５重量％配合したことを特徴とする高層鉄筋コンクリート構造物や鋼管充填コンクリート（ＣＦＴ）構造物等の施工に用いられる設計基準強度８０Ｎ／ｍｍ２程度以下の高強度・高流動コンクリートに関し、シリカヒュームによることなく低水セメント比で高い流動性及び低い粘性を示し、熱履歴を受けた場合でも高い強度発現性を示す高強度・高流動コンクリート用セメントを提供する技術の開示がある。 Patent Document 5 describes a design used for construction of a high-rise reinforced concrete structure, a steel pipe-filled concrete (CFT) structure, or the like, which comprises 2 to 25% by weight of fly ash having a particle size of 20 μm or less in the patent claim. For high-strength, high-fluidity concrete with a standard strength of about 80 N / mm 2 or less, it shows high fluidity and low viscosity at a low water-cement ratio without using silica fume, and shows high strength development even when subjected to thermal history. There is a disclosure of technology to provide cement for high-strength and high-fluidity concrete.
特許文献６には、粉体成分としてポルトランドセメントおよびブレーン比表面積７０００〜３００００ｃｍ２／ｇの石灰石粉、フライアッシュ及び高炉水砕スラグよりなる群から選択された１種以上の無機質高微粉砕粉末を含み、該無機質高微粉砕粉末が該粉体成分に５〜３０重量％含まれていることを特徴とする高強度セルフレベリング性セメント組成物が記載されている。 Patent Document 6 describes one or more kinds of highly finely pulverized inorganic powders selected from the group consisting of Portland cement, limestone powder having a brain specific surface area of 7,000 to 30,000 cm 2 / g, fly ash and blast furnace granulated slag as powder components. A high-strength self-leveling cement composition containing 5 to 30% by weight of the inorganic highly pulverized powder is contained in the powder component.
また、高炉スラグやシリカヒュームを用いたコンクリートにおいて耐火性を上げる技術も知られており、例えば特許文献７〜９記載の発明がある。 Further, a technique for improving fire resistance in concrete using blast furnace slag or silica fume is also known. For example, there are inventions described in Patent Documents 7 to 9.
特許文献７には、セメント、シリカヒューム、細骨材、粗骨材及び高性能減水剤を含み且つ膨張材を含まない、水／結合材比が１０〜１５質量％のコンクリートの圧縮強度の９０％以上の圧縮強度を同一材齢で有する、結合材の一部を膨張材で置換含有させた又は膨張材を添加配合したコンクリートを６０〜９０℃で５日間以上加熱促進養生して製造するにあたり、結合材の０．６〜２．８質量％を膨張材で置換含有させるか又は結合材の０．６〜２．８質量％量の膨張材を添加配合し、コンクリート打設後２４時間以上経過後に、加熱促進養生を行うことを特徴とする、高強度コンクリートの製造方法が記載されており、耐火爆裂抑制材として、ポリプロピレン繊維等の耐火爆裂抑制材を含む実施形態が記載されている。 Patent Document 7 describes 90 of the compressive strength of concrete having a water / binder ratio of 10 to 15% by mass, which contains cement, silica fume, fine aggregate, coarse aggregate and high-performance water reducing agent and does not contain expansion material. When producing concrete having a compressive strength of% or more at the same age, partially containing a part of the binder with an expanding material, or containing an expanding material, and heating and curing at 60 to 90 ° C. for 5 days or more. , 0.6 to 2.8% by mass of the binder is replaced with an expansion material, or 0.6 to 2.8% by mass of the binder is added and blended, and 24 hours or more after the concrete is placed. A method for producing high-strength concrete, which comprises performing heat-accelerated curing after the lapse of time, is described, and an embodiment including a fire-resistant explosion-resistant material such as polypropylene fiber is described as a fire-resistant explosion-resistant material.
特許文献８には、コンクリート構造体に用いられる耐火性コンクリートであって、所定の温度で気化する性質を有するとともに、紐状で、長さと太さの比であるアスペクト比が４１０以上７００以下の有機繊維と、結合材のうち５０重量％以上６０重量％以下の割合で含まれる高炉スラグと、靭性を向上させるための鋼繊維とを含むことを特徴とする耐火性コンクリートが記載されている。 Patent Document 8 describes a refractory concrete used for a concrete structure, which has a property of vaporizing at a predetermined temperature, is string-shaped, and has an aspect ratio of 410 or more and 700 or less, which is a ratio of length to thickness. Described is a refractory concrete characterized by containing organic fibers, blast furnace slag contained in a proportion of 50% by weight or more and 60% by weight or less of the binder, and steel fibers for improving toughness.
特許文献９には、珪酸リチウムを含有することを特徴とする耐火耐熱コンクリートが記載されており、無機添加物として、シリカフューム、高炉スラグ微粉末、天然岩石の微粉末、人口セラミックの微粉末及びフライアッシュ微粉末からなる群から選ばれた１種又は２種以上を配合することが記載されている。 Patent Document 9 describes refractory heat-resistant concrete containing lithium silicate, and as inorganic additives, silica fume, blast furnace slag fine powder, natural rock fine powder, artificial ceramic fine powder and fly. It is described that one or more selected from the group consisting of ash fine powder is blended.
高強度コンクリートの耐火性に関しては、例えば上述した特許文献７〜９などにもあるように、従来、ポリプロピレン繊維などの繊維を加えることが多い。しかしながら、ポリプロピレン繊維を加えることにより、一般にコンクリートのフロー値が低下する傾向がある。 Regarding the fire resistance of high-strength concrete, as described in Patent Documents 7 to 9 described above, conventionally, fibers such as polypropylene fibers are often added. However, the addition of polypropylene fibers generally tends to reduce the flow value of concrete.
本発明は、このような背景のもとに開発されたものであり、高強度モルタルまたは高強度コンクリートの配合において、高炉スラグ微粉末および／またはフライアッシュ微粉末を添加することにより、低水結合材比で高い流動性および低い粘性を示し、かつ耐火性能を持つ高強度モルタルまたは高強度コンクリートを得られる方法の提供を目的としている。 The present invention has been developed against such a background, and low water bonding is performed by adding blast furnace slag fine powder and / or fly ash fine powder in the formulation of high-strength mortar or high-strength concrete. It is an object of the present invention to provide a method for obtaining high-strength mortar or high-strength concrete showing high fluidity and low viscosity in terms of material ratio and having fire resistance.
本発明の高強度モルタルまたは高強度コンクリートの耐火性能の向上方法は、累積体積通過率５０％の粒径が０．５〜５．０μｍである高炉スラグ微粉末および／またはフライアッシュ微粉末を結合材に添加することを特徴とするものである。 The method for improving the fire resistance of high-strength mortar or high-strength concrete of the present invention combines blast furnace slag fine powder and / or fly ash fine powder having a cumulative volume passage rate of 50% and a particle size of 0.5 to 5.0 μm. It is characterized by being added to the material.
高炉スラグ微粉末とフライアッシュ微粉末は、結合材に何れか一方を添加すればよいが、その場合に限らず高炉スラグ微粉末とフライアッシュ微粉末の両者を併用して添加してもよい。 Either one of the blast furnace slag fine powder and the fly ash fine powder may be added to the binder, but not limited to this case, both the blast furnace slag fine powder and the fly ash fine powder may be added in combination.
水結合材比Ｗ／Ｐ１５〜３０％（Ｐ＝Ｎ＋ＡＤ）の高強度モルタルまたは高強度コンクリートに累積体積通過率５０％の粒径が０．５〜５．０μｍである高炉スラグ微粉末および／またはフライアッシュ微粉末を５〜３０％添加することにより高強度モルタルまたは高強度コンクリートの耐火性能を向上させることができる。 High-strength mortar or high-strength concrete with a water-bonding material ratio of W / P 15 to 30% (P = N + AD) and blast furnace slag fine powder with a cumulative volume passage rate of 50% and a particle size of 0.5 to 5.0 μm and / or The fire resistance performance of high-strength mortar or high-strength concrete can be improved by adding 5 to 30% of fly ash fine powder.
高強度モルタルまたは高強度コンクリートの配合において、流動性などのフレッシュ性状の観点からは、水結合材比は好ましくは１７．５〜２５％、より好ましくは２０〜２５％である。 In the formulation of high-strength mortar or high-strength concrete, the water-bonding material ratio is preferably 17.5 to 25%, more preferably 20 to 25%, from the viewpoint of fresh properties such as fluidity.
高炉スラグ微粉末および／またはフライアッシュ微粉末の置換率（ＡＤ／Ｐ）は、５〜３０％が好ましい。置換率が大きい範囲ではフレッシュ性状における流動性が良好であるが、耐火性能の面では、より好ましくは５〜２０％、さらに好ましくは５〜１５％である。 The substitution rate (AD / P) of the blast furnace slag fine powder and / or the fly ash fine powder is preferably 5 to 30%. In the range where the substitution rate is large, the fluidity in the fresh property is good, but in terms of fire resistance, it is more preferably 5 to 20%, still more preferably 5 to 15%.
高炉スラグ微粉末またはフライアッシュ微粉末の累積体積通過率５０％粒径は好ましくは０．５〜３．５μｍ、より好ましくは０．９〜３．２μｍである。累積体積通過率５０％粒径が大きくなるとモルタル化時間が大きくなってしまう傾向があり、また累積体積通過率５０％粒径が小さくなると、混和材料の置換率によっては耐火性能の向上の面で性能がやや低下する傾向がある。 The cumulative volume passage rate of 50% particle size of the blast furnace slag fine powder or fly ash fine powder is preferably 0.5 to 3.5 μm, more preferably 0.9 to 3.2 μm. When the cumulative volume passing rate of 50% particle size increases, the mortarization time tends to increase, and when the cumulative volume passing rate of 50% particle size decreases, the fire resistance performance may be improved depending on the replacement rate of the admixture. Performance tends to be slightly degraded.
本発明の高強度モルタルまたは高強度コンクリートの耐火性能の向上方法における結合材としては、各種ポルトランドセメント、混合セメントなどを用いることができ、またモルタルまたはコンクリートの目的に応じた性能を高めるためにセメントの一部を他の材料に置き換えた各種セメント系材料などにも適用することができる。 Various Portland cements, mixed cements and the like can be used as the binder in the method for improving the fire resistance performance of the high-strength mortar or high-strength concrete of the present invention, and cement is used to enhance the performance of the mortar or concrete according to the purpose. It can also be applied to various cement-based materials in which a part of the above is replaced with another material.
本発明の高強度モルタルまたは高強度コンクリートの耐火性能の向上方法では、累積体積通過率５０％の粒径が０．５〜５．０μｍである高炉スラグ微粉末および／またはフライアッシュ微粉末を結合材に添加することで、シリカフューム微粉末などが添加される場合に比べ、高強度モルタルまたは高強度コンクリートの耐火性能が顕著に向上する。 In the method for improving the fire resistance of high-strength mortar or high-strength concrete of the present invention, blast furnace slag fine powder and / or fly ash fine powder having a cumulative volume passage rate of 50% and a particle size of 0.5 to 5.0 μm are combined. By adding it to the material, the fire resistance performance of high-strength mortar or high-strength concrete is remarkably improved as compared with the case where silica fume fine powder or the like is added.
また、従来、高強度モルタルまたは高強度コンクリートの耐火性能の向上に用いられることがあるポリプロピレン繊維との併用においてもフロー値の低下を抑えつつ、耐火性能を向上させることができる。 Further, even when used in combination with polypropylene fiber, which is conventionally used for improving the fire resistance of high-strength mortar or high-strength concrete, it is possible to improve the fire resistance while suppressing the decrease in the flow value.
以下、本発明の高強度モルタルまたは高強度コンクリートの耐火性能の向上方法を、その効果を確認するために行った試験に基づいて説明する。 Hereinafter, a method for improving the fire resistance of the high-strength mortar or high-strength concrete of the present invention will be described based on a test conducted to confirm the effect.
〔使用材料〕
試験に用いた使用材料を表１に示す。
[Material used]
Table 1 shows the materials used in the test.
〔試験方法〕
試験方法としては、モルタルを作製して評価した。モルタルの配合は、高強度コンクリートの粗骨材を抜いたものとした。材料は表１に示すものを用いた。練混ぜの器具としては一般的に用いられているホバートミキサ（容量３Ｌ、０．１２５ｋｗｈ）を使用した。ミキサに材料を投入した後、フロー試験が可能となるような混合状態と目視できた時間をモルタル化時間として測定した。モルタル化時間を測定した後に９０秒間撹拌した。フロー試験は、JIS R 5201「セメントの物理試験方法」に準拠した方法で行なった。フロー値が２６０±１０ｍｍとなるようにＳＰ添加量を調整した。練り混ぜたモルタルを４×４×１６ｃｍの型枠に成型後、２４時間後に脱型してから材齢7日、２８日まで封函養生した試料(４×４×６ｃｍに切断)を用い、耐火試験を実施した。
〔Test method〕
As a test method, a mortar was prepared and evaluated. The composition of the mortar was such that the coarse aggregate of high-strength concrete was removed. The materials shown in Table 1 were used. A commonly used Hobart mixer (capacity 3 L, 0.125 kwh) was used as the kneading device. After the material was put into the mixer, the mortarization time was measured as the mixed state and the time that could be visually observed so that the flow test could be performed. After measuring the mortarization time, the mixture was stirred for 90 seconds. The flow test was carried out by a method conforming to JIS R 5201 “Physical test method for cement”. The amount of SP added was adjusted so that the flow value was 260 ± 10 mm. After molding the kneaded mortar into a 4 x 4 x 16 cm mold, the sample was demolded 24 hours later and then sealed and cured until the age of 7 days and 28 days (cut into 4 x 4 x 6 cm). A fire resistance test was conducted.
耐火試験は、電気炉に試料を投入して４００℃まで４０℃/分、４００℃〜１１００℃まで１０℃/分で電気炉の温度を上昇させた。１１００℃で７０分保持後、自然冷却させた。電気炉での加熱前後の試料の質量変化率から耐火性能を評価した。質量変化率は、(加熱前の質量−加熱後の質量)÷加熱前の質量×１００で算出した。加熱中の試料の爆裂の評価は、爆裂なし、爆裂あり(試料破片回収可能)、爆裂あり(試料回収不可能)の３種類とした。なお、爆裂あり(試料回収不可能)のときの質量変化率は１００％とした。 In the fire resistance test, the sample was put into an electric furnace and the temperature of the electric furnace was raised at 40 ° C./min to 400 ° C. and 10 ° C./min from 400 ° C. to 1100 ° C. After holding at 1100 ° C. for 70 minutes, it was naturally cooled. The fire resistance was evaluated from the mass change rate of the sample before and after heating in the electric furnace. The mass change rate was calculated by (mass before heating-mass after heating) ÷ mass before heating × 100. There were three types of evaluation of the explosion of the sample during heating: no explosion, with explosion (sample debris can be collected), and with explosion (sample cannot be collected). The mass change rate when there was an explosion (sample recovery was not possible) was set to 100%.
〔試験結果〕
(1) フレッシュ性状
フレッシュ性状の試験結果を表２に示した。混和材の置換率を変化させた水準１〜２５において、混和材の置換率ＡＤ／Ｐ（Ｐ＝Ｎ＋ＡＤ）が５％のときは混和材の種類によらずモルタル化時間が大きくなった。混和材が１５％のときは、Ｆ３．２およびＢＦ１．８以外では９０秒以下とモルタル化時間が短くなった。混和材が２０％以上では、Ｆ３．２以外でモルタル化時間が９０秒以下となり、流動性が良好なモルタルが得られた。
〔Test results〕
(1) Fresh properties Table 2 shows the test results of fresh properties. At levels 1 to 25 in which the substitution rate of the admixture was changed, when the substitution rate AD / P (P = N + AD) of the admixture was 5%, the mortarization time increased regardless of the type of admixture. When the admixture was 15%, the mortarization time was shortened to 90 seconds or less except for F3.2 and BF1.8. When the admixture was 20% or more, the mortarization time was 90 seconds or less except for F3.2, and a mortar having good fluidity was obtained.
水結合材比を変化させた水準２６〜３７において、フライアッシュの粒度が大きく水結合材比が小さい水準３６、３７は、モルタル化時間が大きく、練り混ぜが困難であった。 At levels 26 to 37 in which the water binder ratio was changed, at levels 36 and 37 where the particle size of fly ash was large and the water binder ratio was small, the mortarization time was long and it was difficult to knead.
ポリプロピレン繊維を添加した水準３８〜４３において、シリカフュームにポリプロピレン繊維を０．１５５、０．１３５Ｖｏｌ％（コンクリートで０．１、０．２Ｖｏｌ％相当）の添加で、フロー値が低下した。しかし、フライアッシュ微粉末であるＦ０．９にポリプロピレン繊維を０．１５５、０．１３５Ｖｏｌ％（コンクリートで０．１、０．２Ｖｏｌ％相当）の添加では、フロー値の低下は認められなかった。 At levels 38 to 43 to which polypropylene fibers were added, the flow value was lowered by adding polypropylene fibers to silica fume at 0.155, 0.135 Vol% (corresponding to 0.1, 0.2 Vol% for concrete). However, no decrease in the flow value was observed when polypropylene fibers were added to F0.9, which is a fine powder of fly ash, at 0.155, 0.135 Vol% (corresponding to 0.1, 0.2 Vol% for concrete).
(2) 耐火性能
耐火性能の試験結果を表３に示した。混和材の置換率を変化させた水準１〜２５において、シリカフュームを混和材に使用した場合は、５％添加の材齢２８日以外はすべて爆裂した。フライアッシュ微粉末を添加した場合は、置換率１５％まではＦ０．９の材齢７日の一部を除き爆裂をしなかった。ただし、置換率２５％以上ではいずれも爆裂をした。高炉スラグ微粉末を用いた水準はいずれも爆裂をしなかった。
(2) Fire resistance performance Table 3 shows the test results of fire resistance performance. When silica fume was used as the admixture at levels 1 to 25 in which the substitution rate of the admixture was changed, all of them exploded except for the age of 28 days when 5% was added. When the fly ash fine powder was added, the material did not explode up to a substitution rate of 15% except for a part of F0.9 of 7 days of age. However, when the substitution rate was 25% or more, all of them exploded. None of the levels using blast furnace slag fine powder exploded.
水結合材比を変化させた水準２６〜３７において、シリカフュームを混和材に使用した場合は、いずれも爆裂をした。フライアッシュ微粉末を用いた場合は、Ｆ０．９の一部で爆裂した。ほかの粒度のフライアッシュ微粉末ではいずれも爆裂しなかった。 When silica fume was used as an admixture at levels 26-37 with varying water binder ratios, they all exploded. When fly ash fine powder was used, it exploded at a part of F0.9. None of the other particle size fly ash fine powders exploded.
ポリプロピレン繊維を添加した水準３８〜４３において、シリカフュームを混和材として使用した場合は、ポリプロピレン繊維を添加した水準も含めて爆裂をした。フライアッシュ微粉末Ｆ０．９にポリプロピレン繊維を添加した水準では爆裂をしなかった。 When silica fume was used as an admixture at levels 38 to 43 to which polypropylene fibers were added, the explosion occurred including the level to which polypropylene fibers were added. No explosion occurred at the level where polypropylene fiber was added to fly ash fine powder F0.9.
以上のモルタルのフレッシュ性状に関する試験結果および耐火性能の評価においては、シリカフューム微粉末に比べ、フライアッシュ微粉末および高炉スラグ微粉末が、高強度モルタルまたは高強度コンクリートの耐火性能に関して有効であること、高強度コンクリートの耐火性能の向上に用いられることがあるポリプロピレン繊維との併用においてもフロー値の低下を抑えつつ、耐火性能が向上することが確認された。 In the above test results and evaluation of fire resistance of mortar, fly ash fine powder and blast furnace slag fine powder are more effective than silica fume fine powder in terms of fire resistance of high-strength mortar or high-strength concrete. It was confirmed that the fire resistance performance is improved while suppressing the decrease in the flow value even when used in combination with the polypropylene fiber, which is sometimes used to improve the fire resistance performance of high-strength concrete.
Claims (4)
In the method for improving the fire resistance performance of high-strength concrete according to any one of claims 1 to 3, the binder is cement, or a high-strength mortar or high-strength concrete containing cement. How to improve fire resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019201252A JP7384636B2 (en) | 2019-11-06 | 2019-11-06 | How to improve the fire resistance of high-strength mortar or high-strength concrete |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019201252A JP7384636B2 (en) | 2019-11-06 | 2019-11-06 | How to improve the fire resistance of high-strength mortar or high-strength concrete |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2021075409A true JP2021075409A (en) | 2021-05-20 |
| JP7384636B2 JP7384636B2 (en) | 2023-11-21 |
Family
ID=75897203
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2019201252A Active JP7384636B2 (en) | 2019-11-06 | 2019-11-06 | How to improve the fire resistance of high-strength mortar or high-strength concrete |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7384636B2 (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01280506A (en) * | 1988-01-17 | 1989-11-10 | Toomen Constr Kk | Manufacture of high-strength cement mortar product |
| JP2008189491A (en) * | 2007-02-02 | 2008-08-21 | Sumitomo Osaka Cement Co Ltd | Composition for ultra-high strength mortar, composition for ultra-high strength concrete, and method for producing the composition for ultra-high strength mortar |
| JP2009269786A (en) * | 2008-05-07 | 2009-11-19 | Utsunomiya Univ | Hydraulic composition and concrete using the hydraulic composition |
| JP2012214343A (en) * | 2011-03-31 | 2012-11-08 | Taisei Corp | Spalling-preventable ultra-high strength concrete |
| JP2018127375A (en) * | 2017-02-08 | 2018-08-16 | 株式会社デイ・シイ | Blast furnace slag fine powder and cement composition |
| JP2019026490A (en) * | 2017-07-26 | 2019-02-21 | 太平洋セメント株式会社 | Cement composition |
-
2019
- 2019-11-06 JP JP2019201252A patent/JP7384636B2/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01280506A (en) * | 1988-01-17 | 1989-11-10 | Toomen Constr Kk | Manufacture of high-strength cement mortar product |
| JP2008189491A (en) * | 2007-02-02 | 2008-08-21 | Sumitomo Osaka Cement Co Ltd | Composition for ultra-high strength mortar, composition for ultra-high strength concrete, and method for producing the composition for ultra-high strength mortar |
| JP2009269786A (en) * | 2008-05-07 | 2009-11-19 | Utsunomiya Univ | Hydraulic composition and concrete using the hydraulic composition |
| JP2012214343A (en) * | 2011-03-31 | 2012-11-08 | Taisei Corp | Spalling-preventable ultra-high strength concrete |
| JP2018127375A (en) * | 2017-02-08 | 2018-08-16 | 株式会社デイ・シイ | Blast furnace slag fine powder and cement composition |
| JP2019026490A (en) * | 2017-07-26 | 2019-02-21 | 太平洋セメント株式会社 | Cement composition |
Also Published As
| Publication number | Publication date |
|---|---|
| JP7384636B2 (en) | 2023-11-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Hanumesh et al. | The mechanical properties of concrete incorporating silica fume as partial replacement of cement | |
| JP4834574B2 (en) | Cement composition for high fluidity concrete and high fluidity concrete composition | |
| KR101948627B1 (en) | High strength lightweight concrete composition including artificial lightweight aggregates | |
| KR100873514B1 (en) | Binder for concrete having ultra high strength and a method for manufacturing concrete using the binder | |
| JP6338855B2 (en) | Concrete composition having initial and long-term high strength development and high crack resistance and concrete body using the composition | |
| JP2008184353A (en) | Mortar used for repair and tunnel maintenance and repair method using it | |
| JP6022747B2 (en) | High strength mortar composition | |
| JP5702608B2 (en) | High strength mortar composition | |
| JP2010254556A (en) | Crack self-repairing concrete material and concrete crack self-repairing method using the concrete material | |
| JP6521608B2 (en) | High durability concrete | |
| TW201934518A (en) | High strength grout composition and high strength grout mortar using same | |
| JP2017114734A (en) | Super quick hardening cement mortar | |
| JP2017149639A (en) | Artificial aggregate and cement curing body | |
| JP6985177B2 (en) | Hydraulic composition and concrete | |
| KR101750830B1 (en) | Low viscosity-low heat generation binder and Low viscosity-low mass concrete composition using the same | |
| JP2021075409A (en) | Method of improving fire resistance of high-strength mortar or high-strength concrete | |
| JP3806420B2 (en) | Low strength mortar filler using shirasu | |
| JP5997807B2 (en) | High strength mortar composition | |
| JP5816731B2 (en) | Method for producing high-strength concrete | |
| JP2022015947A (en) | Fiber reinforced cement composition | |
| KR101750831B1 (en) | Low viscosity-low heat generation binder and Low viscosity-low heat generation-high strength concrete composition using the same | |
| JP7187090B1 (en) | concrete composition | |
| JP2010265166A (en) | Environmental load-reducing mortar or concrete kneading matter | |
| JP4953568B2 (en) | Setting accelerator for cement and cement composition | |
| KR101958911B1 (en) | Binder for cement-based hardened product and concrete comprising the same, and structure manufactured by the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20220819 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20230327 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230404 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20230602 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230704 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20230901 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20231107 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20231109 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7384636 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |